import six
if six.PY3:
# There are no need to implement any aditional logic for Python 3.3+, because
# there base class 'object' already have implemented '__dir__' method,
# which could be accessed via super() by subclasses
class DirMixIn:
pass
else:
# implement basic __dir__ to make it assessible via super() by subclasses
[docs] class DirMixIn(object):
""" Mix-in to make implementing __dir__ method in subclasses simpler
"""
def __dir__(self):
# code is based on
# http://www.quora.com/How-dir-is-implemented-Is-there-any-PEP-related-to-that
def get_attrs(obj):
import types
if not hasattr(obj, '__dict__'):
return [] # slots only
if not isinstance(obj.__dict__, (dict, types.DictProxyType)):
raise TypeError("%s.__dict__ is not a dictionary"
"" % obj.__name__)
return obj.__dict__.keys()
def dir2(obj):
attrs = set()
if not hasattr(obj, '__bases__'):
# obj is an instance
if not hasattr(obj, '__class__'):
# slots
return sorted(get_attrs(obj))
klass = obj.__class__
attrs.update(get_attrs(klass))
else:
# obj is a class
klass = obj
for cls in klass.__bases__:
attrs.update(get_attrs(cls))
attrs.update(dir2(cls))
attrs.update(get_attrs(obj))
return list(attrs)
return dir2(self)